The first day of the menstrual cycle is also the first day of your menstrual period and that is the very first day you observe bright red blood. Brown spotting is not considered a menstrual period.
However, some women with spotting several days before their menses may or may not have an issue with hormones and the corpus luteum (short corpus luteum phase).
If you are trying to get pregnant and you have regular spotting before your real period begins, we suggest that in addition to using the ovulation calendar, you also add BBT (basal body temperature) and an ovulation detection kit in order to find out when you get pregnant. If you have a lot of spotting you might want to talk to your Ob-Gyn and assess your progesterone level shortly after presumed ovulation.